On Mon, Feb 24, 2014 at 1:35 PM, Leyan <ouyang.leyan...@hotmail.com> wrote: > On 02/24/2014 05:45 PM, Marco Hugentobler wrote: >>> - GUI: have a tab in project properties where non-default datum >>> transforms would be managed - instead of requiring the user to select >>> the datum transform immediately when the layer was added (and without >>> being able to change the decision later) >> >> I don't have a strong opinion if it should be in project properties or if >> the user should be asked immediately. The immediate selection has been >> implemented following the behaviour of a commercial GIS. However, the >> possibility to change it later easily does also sound good to me. >> >> Btw., congratulations to the merge of the multithreading branch! >> >> Regards, >> Marco > > Hi Marco, > > I struggled quite a lot with the interface of a very famous commercial GIS > on this issue, I believe there is a real possibility to do better here ! I > think it is essential to allow the user to change the transformation later > easily, maybe somewhere linked from the CRS choice ? That's where I would go > as a user. > > I was also wondering how you see the relationship between CRS and datum > transformation. I use CRSs (all the Beijing54 CRS) which already have a > +towgs84 defined in their definition, but several towgs84 coefficients are > offered when loading the layer. It is confusing to have to answer that, and > if something else than the default coefficients is chosen, the result is > incompatible with the proj4 definition. Should we strip these CRS > definitions of the towgs84 coefficients (which were only meant for a small > area initially, so are not valid everywhere)?
Please note the following related issue: http://hub.qgis.org/issues/9396 "deactivate the Select datum transformations dialog by default" Maybe the ticket has to be reopened? Best wishes, Anita _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer